Magnum action

there is a rather pronounced taper in the diameter of the case from the space in front of the belt down to the shoulder in the H&H,
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which is intentional....

If you look at the H&H, and the other African "Express" rounds of the era (and before and after) you'll see nearly all of them are very tapered. ALSO, they are loaded to "moderate" pressures, not the high intensity pressures of modern magnums.

Those designers in England and on the continent were not dummies, and they knew what they were making those rounds for. AFRICA. Where temps regularly were over 100, and many preferred double rifles, so "stopping" ammo was deliberately made tapered and moderate pressure to aid in extracting fired cases.

People desiging big magnum rifle cases 50 or 100 years later had the benefit of more advanced technology (rifles and ammo) and a somewhat different primary market.

The .375 H&H is into its second century now, and while you can get things that out perform it, I wonder why you would need to...;)
 
Yeah, I'm still (over)thinking about this. The RUM cartridges are based on the 404 Jeffery, of course, but they use a rebated rim of the common 0.532 vs. the original 0.543. I like the elimination of the stress riser belt, although through many years of loading 7mm Rem Mag and 338 Win Mag (and a year of 8mm Rem Mag) I've never had a case start thinning out ahead of the belt. That argues for the 8mm Mag, which I really do like. I'd just have to send one of my 700s to a new home. Already have some good loads, and that little voice keeps telling me, "Dummy, you can't shoot that far". And if I could, something would eat my game before I could get these old bones way over there. (Unless I had a horse, but horses don't like me.)

Which brings me to: My unicorn cartridge is the 404 Jeffery. And I have exactly as much practical use for it as I do for one of the RUMs or another 8 Mag. How much trouble is it to open a bolt face 0.01"?
 
I believe that there are a range of tolerances in magnum bolt head walls so that they can accommodate +/- a couple thousandths--scorch would know.
 
which is intentional....

If you look at the H&H, and the other African "Express" rounds of the era (and before and after) you'll see nearly all of them are very tapered. ALSO, they are loaded to "moderate" pressures, not the high intensity pressures of modern magnums.

Those designers in England and on the continent were not dummies, and they knew what they were making those rounds for. AFRICA. Where temps regularly were over 100, and many preferred double rifles, so "stopping" ammo was deliberately made tapered and moderate pressure to aid in extracting fired cases.

People desiging big magnum rifle cases 50 or 100 years later had the benefit of more advanced technology (rifles and ammo) and a somewhat different primary market.

The .375 H&H is into its second century now, and while you can get things that out perform it, I wonder why you would need to...
Click to expand...
Agree 100%--except that as the H&H became the father of derived cartridges--issues can arise with adapting its design to modern chambers and actions. Run into them myself. No argument from me that it is absolute classic.
 
Several have hinted at it, but true magnum actions are quite rare. None of the USA made actions are true magnum actions even though some are offered in 375 H&H. To make it work they use 30-06 length actions that are modified at the factory by machining the loading/ejection port larger as well as modifying the magazine box. Once the loading/ejection port is enlarged the hole spacing for scope mounting is also different. But they start with a basic long action.

So, what type of action is it, who manufactured it? Knowing that, instead of calling it a generic magnum action would clear up confusion. There are a handful still made in Europe and some older rifles out there with true magnum actions.
 
CZ 550, but I did say magnum length action, meaning I want to take advantage of it to load rounds with a 0.532 bolt face and a maximum COL of about 3.6. I only have 2 such rounds now, 8mm Rem Mag running in Remington 700 BDLs of '77-'78 vintage, and 416 Rem Mag running in a newer Portuguese Model 70. Those may not be "true" magnum actions, but they seem to do OK. And I doubt the BRNO action will be challenged by anything I am considering. (And I'll probably be considering until I put my money down for a barrel.)

I do appreciate the discussion, folks. It keeps my out of the bars, and it costs nothing (yet).
 
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Not going as planned

First, this is not keeping me out of the bars, and second, the CZ action that I was sure to win because I bid too much ran up over $1k. So, new plan.

The photo shows 3 700s, all "magnum" sized. The top one, for those who recommended it, is a 300 H&H (aka 30 Super) "Classic". I started load workup yesterday and found it a little slow compared to published numbers and Quickload. Decent accuracy, but more work to do. But I think Remington's Classic version of the 700 is elegant. I'll make it sing.

The others are my 8mm Rem Mags. My other chore yesterday was to run a shootoff to determine which went for a barrel transplant. One of those rifles came with Nosler Custom ammo in both Accubond and Partition varieties, and I chose to expend the Partitions. The one without irons that I have had for a few months was the clear winner, so the other one is going for a 338 Rem Ultra Mag barrel. Whose barrel and where to do the work is TBD.

I do plan to keep the stock and install a crossbolt behind the recoil lug. I haven't done that before, but I have done plenty of drilling on centers for muzzleloader pins and screws. And if it doesn't work out, Bell & Carlson has a bunch of stocks to fit 700s. So, here we go again.
 

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Powder I have. But I'm almost down to my last thousand CCI 250. Given the current lead time for new barrels, that may not be a problem. Meanwhile, I'll have fun with the 8 Mag and my pedestrian 338 Win Mags.
 
You have to be a vigilant internet sniper willing to take the shot fast and at high--possibly outrageous--prices when they become briefly available.
 
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